Various fiber aggregates are known, including those for use in applications such as concrete composites, filtration, and absorption.
In another aspect, various multi-component fibers are known. Useful properties of some of these fibers include fiber bonding, wherein for example, a low melting or softening sheath covers a higher melting core. The sheath, when melted or softened serves as a bonding agent for the core.
In another aspect, oil and gas field operators have a need for controlling proppant flowback. Several different approaches have been used to solve this problem, including the use of resin coated (e.g., the coating may be thermosetting resins, such as epoxies and phenolics, and thermoplastic elastomers, such as acrylic resins) proppants. The coated proppants are expected to adhere to each other at the down hole to form an integrated proppant block in down hole. A disadvantage of resin coated proppants for proppant flowback control is the potential premature curing of the proppants, as well as compatibility with the components of hydraulic fracture fluid, such as breakers.
Relatively short fibers (see, e.g., U.S. Pat. No. 5,330,005 (Card et al.), U.S. Pat. No. 5,501,275 (Card et al.), and U.S. Pat. No. 6,172,011 (Card et al.)) have been applied to flowback control. A disadvantage of this approach is its efficiency in controlling flowback. Other approaches have been proposed, such as inclusion of short fibers in the resin coated layers on the proppant, and the modification of proppant geometry including the aspect ratio and particle size distribution.
There is a need for additional flowback control options.